• Skip to main content
  • Skip to secondary menu
  • Skip to primary sidebar

Mechanicaleng blog

siemens nx tutorial & injection molding technology

  • Plastic molding
  • Siemens nx
    • nx modeling
    • nx drafting
    • nx sketching
    • nx assembly
  • Mechanical basic
    • mechanical standard
    • Mechanism video
  • microsoft office
    • microsoft word
    • powerpoint
    • excel tips
  • About me
  • CONTACT ME
Home » Mechanism » what is a pulley system | simple machine

what is a pulley system | simple machine

March 10, 2020 by mechanicaleng blog Leave a Comment

Pulley system is  very popular and simple machine. It use to change movement direction of cable and can reduce heavy object. A pulley system has a wheel with a groove on an axle or shaft that is designed to support movement , and a rope in the groove.

Post contents

  • I. What are the 3 types of pulleys?
    • 1. Fixed pulley.
    • 2. Movable Pulley.
    • 3. Compound pulley.
  • II. How does pulley system work?
  • III. What is the formula for a pulley system?

I. What are the 3 types of pulleys?

There are three types of pulleys. Each pulley system depends on how the wheel and rope are put together: fixed, movable, and compound.

1. Fixed pulley.

Fixed pulley

This is the simplest system. The place of the pulley is fixed, the wheel can rotate in axis only, the rope moved in the groove of the pulley.

2. Movable Pulley.

Movable Pulley 01

In this case, the object and pulleys can move from place to plate. One end of the rope is attached to a fixed point that does not move.

3. Compound pulley.

It is combined pulleys. In the compound pulley has fixed and movable pulley.  It is a combination of pulleys that make the effort less than half of the weight of the load.

II. How does pulley system work?

* Fixed pulley.

+ Using the screws and a screwdriver or drill, to attach the pulley on the place.

+ Through the rope in the groove of the pulley.

+ One end of the rope attach to the object. You can use your hand or machine to pull down on the free end of the rope.  When you pull down the rope, the wheel will rotate on the axis and the object will move up.

* Movable Pulley.

+ Using the screws and your screwdriver or drill, attach one fixed pulley on the place.

+ Feed the rope through the pulley, and feed the rope through the movable pulley, and fixed one end the rope  on the fix place.

+ Attached the object on the movable pulley.

+ You can use your hand or machine to pull down on the free end of the rope.  When you pull down the rope, the wheel will rotate on the axis and the object and movable pulley will move up.

You can see these video below for understanding: How does pulley system work?

 

III. What is the formula for a pulley system?

For fixed pulley.

As this picture below, we have to move an object with single pulley, and we will calculate the force without friction between the wheel and rope.

Formula for a pulley system- Fixed pulley

M: Mass (kg)

g: acceleration of gravity (m/s²), g = 9.81 m/s²

F: Force to pull the object.(N)

α: angle of the rope.

We can calculate the force as formula:   F = Mg/cos(α) = 9.81 M/ cos(α)

For the example, M = 1o kg, α = 60 degree -> F = 10*9.81/cos(60) = 98.1* 2 = 196.2 N

For Movable Pulley and compound pulley.

Movable Pulley

M: Mass (kg)

g: acceleration of gravity (m/s²), g = 9.81 m/s²

F: Force to pull the object.(N)

n: number of the wheel

We can calculate the force as formula:   F = Mg/n = 9.81M/n

For the example, M = 1o kg, n=2 -> F = 10*9.81/2 = 98.1/ 2 = 49.05 N

Related posts:

Belt pulley mechanism example 710 belt and pulley mechanism examples simple planetary gear setsimple planetary gear set how to work and calculate Default Thumbnail[Video] How to simple slider crank mechanism work Default ThumbnailInventor draft command tutorial

Filed Under: Mechanism Tagged With: pulley

Reader Interactions

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

Primary Sidebar

Recent Posts

  • How to create thread in nx
  • nx assembly| create a new part from the same part
  • how to calculate sum of squares in Excel
  • How to active GC toolkits in Siemens NX
  • How to create a sphere in nx
  • How to create a cone in nx
  • How to create a cylinder in nx
  • 3 ways to create a block in NX
  • How to add applause in PowerPoint
  • 4 ways to break line in excel

Copyright © 2022 · Magazine Pro on Genesis Framework · WordPress · Log in