GEAR

Recently I have some chances to attend courses about Gear technology in Industrial Technology Research Institute (工業技術研究院) located in Taichung. The classes held in Chinese, so it's a bit tough for me to follow, but still I found it interesting. In this post, I am trying to compile information about GEAR and hope this will be useful.

A. WORM GEAR.

      This type of gear is normally used when the high ratio is desired. Following video from Dr. E shows some information about it. [1]




Here is the component of worm gear [2].
Application of worm gear: 
  • Hoisting machines
  • Automobile steering mechanisms
  • Elevator
  • Conveyors
  • Packaging machine
  • Presses
If you wish to understand the calculation behind worm gear's design, you may want to check this page.


B. BEVEL GEAR

    Normally Bevel Gear is used when the power of one shaft must be transferred at different angle to another shaft. See below animation for better understanding. [3]


Bevel Gear can be categorized into 4 types as shown at following picture [4]:



Application of Bevel Gear:
  • Automobile differential
  • Hand drill
  • Metal planer
If you wish to learn more about the design calculation of Bevel Gear, you may want to check this page.[4]


C. PLANETARY GEAR.

     Planetary Gear which also known as Epicyclic Gear looks more complicated than the other two gears mentioned above. It consists of several gears rotating inside a circled ring. Following video from youtube, shows the mechanism of the planetary gear.[5]




Following picture puts the components of planetary gear in detail[6]. You may see different naming on each gears, e.g.: sun gear, planet gear, and ring gear. 


Planetary gear applications are as following:

  • Vehicle differential transmission units
  • Multi-input functions generators
  • Robot wrist joints
  • Electric screw driver
If you wish to know further about planetary gears design calculation, you may want to check following link.

These two videos give some examples on how to calculate the speed ratio of the planetary gear.[7,8]

Example 1



Example 2



References:

[1] https://www.youtube.com/watch?v=iu1wAFbGNgY
[2] http://upload.wikimedia.org/wikipedia/commons/0/04/Face_Worm_Gear.jpg
[3] https://www.youtube.com/watch?v=ymHzbN1oK1w
[4] http://www.robotpark.com/academy/robotic-mechanisms-bevel-gears-51035/
[5] https://www.youtube.com/watch?v=UakeTEJlXGw
[6] http://www.beam-wiki.org/wiki/Gear_train
[7] https://www.youtube.com/watch?v=XaBLGdNxQYY
[8] https://www.youtube.com/watch?v=R6lwagjf-vM

Update history:
1. 29-04-2017, fixed broken link, refer to other source [4].
2. 29-04-2017, fixed broken link, upload picture of planetary gear.

Comments

Post a Comment

Popular posts from this blog

GD&T

Image
GD&T stands for Geometric Dimensioning and Tolerancing and is written in  ASME Y14.5-2009.  The GD&T is used often in creating detail 2D drawing and is very powerful tools to ensure that the product will be correctly manufactured.  See below for the most used GD&T symbols. 
Read more

CLEANLINESS OF A CLEAN ROOM

Image
When people designing for a product that is going to be used in the clean room environment, one thing that must be put into consideration is how to let the product itself has a very little of contamination. This is very important because when the product attracts contamination, it will affecting the end product of chip production, i.e.: contaminating the wafer which resulting in defects thus yield lost. First of all, one might want to understand how the clean room being classified. So below (taken from wikipedia ), you may find that the cleanliness of a clean room is segmented into how many contamination accepted in an area. Normally the chip manufacturer will need to define the cleanliness of their fab by judging from the application they will use. The smaller the overlay , the cleaner they want to go.  For example, in 2007 there is a news , Intel aimed to produce a 45nm chips, for this, they came up with a clean room class 1 in about 184,000 square feet, meaning that the
Read more

Photolithography

Image
The word lithography comes from the Greek  lithos , meaning stones, and  graphia , meaning to write. It means quite literally writing on stones. In the case of semiconductor lithography (also called photolithography) our stones are silicon wafers and our patterns are written with a light sensitive polymer called a photoresist. To build the complex structures that make up a transistor and the many wires that connect the millions of transistors of a circuit, lithography and etch pattern transfer steps are repeated at least 10 times, but more typically are done 20 to 30 times to make one circuit. Each pattern being printed on the wafer is aligned to the previously formed patterns and slowly the conductors, insulators, and selectively doped regions are built up to form the final device. [1] The steps used in photolithography is well described at following figures. [2] Intel has this nice simple way of description for the photolithography process in video.  SOURCE: INTEL
Read more