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

베어링은 두 부품 사이의 상대적인 움직임을 허용하는 동시에 기계의 마찰과 마모를 줄이는 기계 요소입니다.
또한 방사형, 축 방향 또는 둘의 조합일 수 있는 하중을 분산하는 데 도움이 됩니다.
피벗 베어링은 회전축의 축 방향 하중을 지지합니다. 그들은 평평하거나 원뿔형 또는 잘린 표면을 가질 수 있습니다.
총 베어링 면적이 πR2인 축 방향 하중을 받는 플랫 피봇 베어링을 생각해 보십시오.
베어링에 가해지는 균일한 압력은 베어링 영역에 대한 하중의 비율로 표현됩니다.
다음으로, 베어링 영역 내에서 반지름 r과 두께 dr의 극소 링을 고려하십시오. 링에 전달되는 하중을 추정할 수 있습니다.
이제 링의 슬라이딩에 저항하는 마찰력은 반경 r에서 접선으로 작용합니다.
따라서 링의 모멘트를 계산하고 반경 방향 한계 내에서 적분함으로써 마찰력을 극복하는 데 필요한 샤프트의 모멘트를 추정할 수 있습니다.

<ol>
	<li>히벨러, R.C. (2016). Engineering Mechanics \u2012 정역학 및 동역학. 뉴저지 호보켄: 피어슨 프렌티스 홀. 447쪽.</li>
</ol>

피벗 베어링

Pivot Bearings

기계 시스템에서 베어링은 마찰과 마모를 최소화하면서 두 구성 요소 간의 상대 운동을 촉진하는 데 매우 중요합니다. 베어링은 기계 부품 전반에 다양한 하중(방사형, 축형 또는 두 하중의 조합)을 분산시켜 원활하고 효율적인 작동을 보장합니다.
피봇 베어링은 회전축에 축방향 하중을 지지하도록 설계된 특수한 유형의 베어링입니다. 베어링 표면, 즉 피봇은 축의 끝에 위치하여 축 추력을 지지합니다. 피봇은 용도에 따라 평평한 표면, 원뿔형 또는 잘린 표면을 특징으로 할 수 있습니다.
플랫 피봇 베어링에서는 축방향 하중을 받으면 베어링에 가해지는 균일한 압력을 베어링 면적에 대한 하중의 비율로 계산할 수 있습니다. 이러한 압력 분포는 베어링 표면의 마찰과 마모를 최소화하여 보다 효율적인 작동과 더 긴 사용 수명에 기여합니다.
평평한 피벗 베어링에 작용하는 힘을 더 분석하기 위해, 우리는 베어링 영역 내에서 반경 r과 두께 dr의 무한소 링을 조사할 수 있습니다. 이 링으로 전달되는 하중은 베어링 표면의 압력 분포를 기반으로 추정할 수 있습니다.
축이 회전함에 따라 마찰력은 고리의 미끄러짐에 저항하고 반지름 r에서 접선방향으로 작용합니다. 고리의 모멘트를 계산하여 반지름 한계 내에 적분하면 축의 모멘트는 다음과 같이 결정됩니다.
<img alt="Equation 1" src="/files/ftp_upload/14324/14324_Equation_1v2.svg" style="text-align: center; height: 28px;" />
이 계산은 다양한 하중 조건에서 베어링의 성능과 효율에 대한 귀중한 통찰력을 제공합니다.
피벗 베어링은 회전축의 축방향 하중을 지지하는 독특한 특성으로 인해 다양한 산업 및 기계 시스템에 사용됩니다. 이러한 다용도 부품은 터빈, 발전기, 펌프와 같은 회전 기계 및 조향 시스템 및 변속기 어셈블리와 같은 자동차 부품에 사용됩니다. 또한 착륙 기어 및 비행 제어 표면을 포함한 피벗 베어링은 항공 우주 분야에서 매우 중요합니다. 또한 크레인, 윈치 및 컨베이어와 같은 산업 장비도 효율적인 작동과 안정적인 성능을 위해 피벗 베어링에 의존합니다. 따라서 다양한 부문에 걸쳐 피벗 베어링이 널리 사용됨에 따라 원활하고 효율적인 기계 시스템을 유지하는 데 중요성이 강조됩니다.

기계 시스템에서 베어링은 마찰과 마모를 최소화하면서 두 구성 요소 간의 상대적인 움직임을 촉진하는 데 중요합니다. 그들은 도움이 ...

Education

교육

JoVE Core

Mechanical Engineering

기계공학

Unit 1

제1단원

Friction

마찰

KEY TERMS AND CONCEPTS

주요 용어 및 개념

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

Static friction is the force that keeps two surfaces from starting to slide past each other. It acts when there is a tendency for motion, but not yet actual slipping. This force helps explain everyday actions like walking on the ground and driving a car. A towing example shows how static friction changes as force is applied. A truck pulls a car with a rope, and the car stays still at first. The car is in static equilibrium, which means the forces on it are balanced. Gravity and the normal...

kinetic friction

Sliding Friction Between Moving Surfaces

Kinetic friction is the sliding friction that acts when two surfaces move against each other. It opposes relative motion and acts parallel to the contact surface, in the opposite direction of travel. In the truck and car example, the car first stays still because static friction holds it in place. When the truck’s force becomes greater than the limiting static frictional force, the friction at the contact surface drops to a lower value. The car then begins to slide, and its speed increases. At...

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

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upward impending motion

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self-locking screw

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screw: problem solving

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frictional forces on flat belts

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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

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bearings: problem solving

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rolling resistance

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rolling resistance: problem solving

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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 Mechanical Engineering offers concise, easy-to-understand animated videos covering key topics such as equilibrium, forces, truss analysis, and structural mechanics. Explore their real-world applications, and witness these concepts in action through scientist-led experiments.

mechanical engineering

Axial Load Support in Pivot Bearings

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