Name: hydraulic hoist force analysis
Uploaded: 2023-09-22T11:49:25.000Z
Duration: 1 min 26 s
Channel: JoVE

שקול מנוף הידראולי התומך בעומס.
בהנחה של ייצוג סכמטי פשוט של מבנה מסגרת זה, איזה כוח פועל על איברי BD ו- BF, בתנאי שמידות האיבר ומשקל העומס ידועים?
כאן, BF ו- BD הם שני חברי כוח, בעוד EFG ו- EDC הם חברים רב-כוחיים.
דיאגרמת גוף חופשי עבור החבר EFG המציינת את כל הכוחות מצוירת.
המרכיבים האנכיים והאופקיים של הכוח FBF ניתנים לביטוי באמצעות משולש שיפוע.
מצב שיווי המשקל ברגע במפרק E נותן את הכוח F BF .
לאחר מכן, ביישום תנאי שיווי משקל הכוח האופקי במפרק E, מוערך כוח התגובה האופקי ב- E.
באופן דומה, תנאי שיווי משקל הכוח האנכי נותן את כוח התגובה האנכי במפרק E.
כעת, בציור דיאגרמת גוף חופשי עבור החבר EDC, ניתן לבטא את מרכיבי הכוח לאורך BD באמצעות משולש שיפוע אחר.
החלת תנאי שיווי משקל הרגע בנקודה C, הכוח F BD מחושב.

<ol>
	<li>היבלר, R.C. (2016). מכניקה הנדסית - סטטיקה ודינמיקה. הובוקן, ניו ג'רזי: אולם פירסון פרנטיס. עמ' 305.</li>
	<li>באר, פ"פ; ג'ונסטון, א.ר.; מזורק, ד"ו; קרומוול, פי ג'יי ועצמי, ב. (2019). מכניקה וקטורית למהנדסים - סטטיקה ודינמיקה. ניו יורק: מקגרו-היל. עמ' 330</li>
	<li>Meriam, J.L., Kraige, L.G. ו- Bolton, J.N. (2020). מכניקה הנדסית - סטטיקה. הובוקן, ניו ג'רזי: ג'ון ווילי. עמ' 200</li>
</ol>

לא הוכרז על ניגוד עניינים.

מסגרות: פתרון בעיות ii

<div style="direction:rtl">

חשבו על מנוף הידראולי התומך בעומס של 1 קילו-ניין. בהנחה של ייצוג סכמטי מפושט של מבנה המסגרת הזה, ניתן לקבוע את הכוח הפועל על איברי BD ו-BF.
<img alt="Figure 1" src="/files/ftp_upload/14292/14292_PT_Fig_1v2.svg" style="text-align: center; height: 350px;"> 

מידות האיבר ומשקל העומס הם פרמטרים ידועים. מבנה זה יכול להיחשב כמסגרת עם BF ו-BD הפועלים כאיברים דו-כוחיים, בעוד שEFG ו-EDC הם איברים מרובי כוחות.

תרשים גוף חופשי עבור האיבר EFG מחושב. את הכוח הנטוי FBF ניתן לפתור לתוך הרכיבים האנכיים והאופקיים. תנאי שיווי משקל המומנט מוחל על מפרק E. 
<img alt="Equation 1" src="/files/ftp_upload/14292/14292_PT_Equation_1v2.svg" style="text-align: center; height: 15px;"> 

הכוח FBF מחושב לפי 1.546 kN. לאחר מכן, מצב שיווי משקל הכוח האופקי מוחל במפרק E. 
<img alt="Equation 2" src="/files/ftp_upload/14292/14292_PT_Equation_2v2.svg" style="text-align: center; height: 15px;"> 

החלפת הערך של הרכיב האופקי של FBF במשוואת שיווי המשקל, כוח התגובה האופקי בE מחושב כ-0.375 kN. באופן דומה, מוחל תנאי שיווי משקל הכוח האנכי. 
<img alt="Equation 3" src="/files/ftp_upload/14292/14292_PT_Equation_3v2.svg" style="text-align: center; height: 15px;"> 

כוח התגובה האנכי המחושב במפרק E הוא 0.500 kN. 

עכשיו, דיאגרמת גוף חופשי עבור האיבר EDC מחושב. ניתן לבטא את הרכיבים האופקיים והאנכיים של FBD באמצעות משולש שיפוע. מוחל תנאי שיווי המשקל של מומנט בנקודה C. 
<img alt="Equation 4" src="/files/ftp_upload/14292/14292_PT_Equation_4v2.svg" style="text-align: center; height: 15px;"> 

הכוח FBD מחושב כ-1.677 kN.

</div>

מסגרות: פתרון בעיות II

שקול מנוף הידראולי התומך בעומס של 1 kN. בהנחה של ייצוג סכמטי פשוט של מבנה מסגרת זה, הכוח הפועל על BD ו ...

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Structural Analysis

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Frames: Problem Solving II

hydraulic hoist force analysis

Hydraulic hoist force analysis shows how to find the forces in key members of a simple frame. The load is 1 kN, and the structure is represented with known member dimensions. In this setup, BF and BD act as two-force members. EFG and EDC are multi-force members, so each one is analyzed with a free-body diagram.

The first step is to study member EFG. The inclined force in BF is split into vertical and horizontal parts. Then the moment equilibrium condition is applied at joint E. Using this step, the force in BF is found to be 1.546 kN.

Next, the horizontal force equilibrium at joint E is used. The horizontal part of the BF force is substituted into the equation. This gives the horizontal reaction force at E as 0.375 kN. The vertical force equilibrium at the same joint is also applied. The vertical reaction force at E is calculated as 0.500 kN.

A free-body diagram for member EDC is then considered. The horizontal and vertical parts of FBD are written using a slope triangle. Finally, the moment equilibrium condition at point C is applied. This calculation gives the force in BD as 1.677 kN.

Hydraulic Hoist Force Analysis

introduction to structures

Structure Types and Force Paths

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Truss member forces can be found with the method of sections in a symmetrical roof truss. The structure here includes vertical, diagonal, and horizontal members. Each horizontal member is 4 m long. The vertical members FB and HD are 4 m long, and member GC is 6 m long. The roof truss carries loads at several joints. Joints F, G, and H each have a 2 kN load. Joints A and E each have a 1 kN load. To start the analysis, moment equilibrium is used at point A. The force and distance values are...

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frames: problem solving ii

Hydraulic hoist force analysis shows how to find the forces in key members of a simple frame. The load is 1 kN, and the structure is represented with known member dimensions. In this setup, BF and BD act as two-force members. EFG and EDC are multi-force members, so each one is analyzed with a free-body diagram. The first step is to study member EFG. The inclined force in BF is split into vertical and horizontal parts. Then the moment equilibrium condition is applied at joint E. Using this...

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key terms and concepts

Analyze a hydraulic hoist frame with free-body diagrams, equilibrium equations, and two-force members to find forces in BF, BD, and reactions at E.

Hydraulic Hoist Force Analysis | 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.

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Hydraulic Hoist Force Analysis

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