Name: axial load support in pivot bearings
Uploaded: 2025-05-22T09:06:04.000Z
Duration: 1 min 23 s
Channel: JoVE

ベアリングは、機械の摩擦と摩耗を減らしながら、2つの部品間の相対運動を可能にする機械要素です。
また、ラジアル、アキシャル、またはその両方の組み合わせである可能性のある荷重を分散するのにも役立ちます。
ピボットベアリングは、回転シャフトの軸方向荷重を支えます。それらは、平ら、円錐形、または切り捨てられた表面を有することができる。
合計ベアリング面積がπR2の軸方向荷重を受けるフラットピボットベアリングを考えてみましょう。
ベアリングにかかる均一な圧力は、ベアリング領域に対する荷重の比率として表されます。
次に、軸受領域内の半径 r と厚さ dr の無限小リングを考えます。リングに伝達される荷重を推定できます。
ここで、リングの滑りに抵抗する摩擦力は、半径rで接線方向に作用します。
したがって、リングのモーメントを計算し、それを半径方向の限界内で積分することにより、摩擦力を克服するために必要なシャフトのモーメントを推定できます。

<ol>
	<li>ヒベラー、RC(2016)。エンジニアリングメカニクス \u2012 静力学と力学。ニュージャージー州ホーボーケン:ピアソンプレンティスホール。447ページ。</li>
</ol>

ピボットベアリング

Pivot Bearings

機械システムにおいて、ベアリングは二つの部品間の相対的な運動を可能にし、摩擦や摩耗を最小限に抑えることが重要です。彼らは様々な荷重（軸方向、軸方向または両方の組み合わせ）を機械部品に分散し、スムーズで効率的な運転を保証します。

ピボットベアリングは、回転軸上の軸方向荷重をサポートするために設計された特殊なタイプのベアリングです。ベアリング面またはピボットは、軸の端に配置され、軸方向の推力を支えます。ピボットは、アプリケーションに応じて平らな、円錐形、または切り詰められた表面を持つ場合があります。

平らなピボットベアリングでは、軸方向荷重が加わると、ベアリングにかかる均一な圧力をベアリング面積への負荷の比率として計算することができます。この圧力分布は、ベアリング面の摩擦や摩耗を最小限に抑え、より効率的な運転と長い寿命に貢献します。

平らなピボットベアリングに作用する力をさらに分析するために、ベアリング面積内の微小なリングを半径r、厚さdrで検討することができます。ベアリング面積全体にわたる圧力分布に基づいて、このリングへ伝わる荷重を推定することができます。

軸が回転すると、摩擦力がリングの滑りを抵抗し、半径rで接触します。リングのモーメントを計算し、半径の範囲内で積分することにより、軸のモーメントは次のように決定されます。<img alt="Equation 1" src="/files/ftp_upload/14324/14324_Equation_1v2.svg" style="text-align: center; height: 28px;" />

この計算により、異なる荷重条件下でのベアリングの性能と効率に関する貴重な知見を得ることができます。

ピボットベアリングは、回転軸上の軸方向荷重をサポートする独特な能力により、さまざまな産業や機械システムで使用されています。これらの多目的な部品は、タービン、発電機、ポンプ、自動車のステアリングシステムやトランスミッションアセンブリなどの回転機械、着陸装置やフライト制御表面を含む航空宇宙アプリケーションで重要です。クレーン、ウインチ、コンベアなどの産業機器も、効率的な運転と信頼性の高いパフォーマンスのためにピボットベアリングに頼っています。結果として、さまざまなセクターでピボットベアリングが広範に使用されていることは、スムーズで効果的な機械システムの維持におけるその重要性を強調しています。

機械システムでは、ベアリングは、摩擦と摩耗を最小限に抑えながら、2つのコンポーネント間の相対運動を促進するために重要です。彼らは助けます...

Education

JoVE Core

Mechanical Engineering

機械工学

Unit 1

ユニット1

Friction

摩擦

KEY TERMS AND CONCEPTS

主要用語と概念

axial load support in pivot bearings

Pivot bearings support axial loads on a rotating shaft. A bearing helps two parts move relative to each other while reducing friction and wear. In this design, the pivot is placed at the end of the shaft to carry the axial thrust.

The pivot surface can be flat, conical, or truncated, depending on the application. In a flat pivot bearing, the axial load is spread over the bearing area. The pressure is uniform and can be found by dividing the load by the area.

To study the forces more closely, engineers can look at a tiny ring inside the bearing surface. This ring has a radius r and a small thickness dr. The load on the ring depends on the pressure across the bearing area.

As the shaft turns, friction acts on the ring and resists sliding. This force acts tangentially at radius r. By finding the moment of the ring and integrating across the radial limits, the moment of the shaft can be determined. This helps explain how the bearing performs under different load conditions.

Pivot bearings are used in many machines and industries. They appear in turbines, generators, pumps, steering systems, and transmission assemblies. They are also important in aerospace parts such as landing gear and flight control surfaces, as well as in cranes, winches, and conveyors.

Axial Load Support in Pivot Bearings

dry friction

Dry Friction in Crates and Everyday Motion

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static friction

Static Friction at the Point of Slip

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kinetic friction

Sliding Friction Between Moving Surfaces

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characteristics of dry friction

Static and Kinetic Dry Friction

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types of friction problems

Dry Friction in Crate, Ladder, and Frame Problems

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friction: problem solving

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frictional forces on screws

Square-Thread Screw Mechanics and Friction

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upward impending motion

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self-locking screw

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flat belts: problem solving

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pivot bearings

Pivot bearings support axial loads on a rotating shaft. A bearing helps two parts move relative to each other while reducing friction and wear. In this design, the pivot is placed at the end of the shaft to carry the axial thrust. The pivot surface can be flat, conical, or truncated, depending on the application. In a flat pivot bearing, the axial load is spread over the bearing area. The pressure is uniform and can be found by dividing the load by the area. To study the forces more closely,...

collar bearings

Friction Torque in Collar Bearings

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journal bearings

Friction Moment in Journal Bearings

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bearings: problem solving

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rolling resistance

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rolling resistance: problem solving

Lawn Roller Force Calculation

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key terms and concepts

Learn how pivot bearings support axial loads on rotating shafts, reduce friction, and appear in turbines, generators, pumps, cars, aircraft, and industrial equipment.

Axial Load Support in Pivot Bearings | JoVE K12

JoVE Core 機械工学は、平衡、力、トラス解析、構造力学などの重要なトピックをカバーする簡潔でわかりやすいアニメーション ビデオを提供します。実際のアプリケーションを探索し、科学者主導の実験を通じてこれらのコンセプトが実際に動作しているのを目撃してください。

mechanical engineering

Axial Load Support in Pivot Bearings

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