Category: 

What Is a Camshaft?

Article Details
  • Written By: Parker Brown
  • Edited By: Lauren Fritsky
  • Last Modified Date: 24 July 2014
  • Copyright Protected:
    2003-2014
    Conjecture Corporation
  • Print this Article
Free Widgets for your Site/Blog
FDA guidelines allow an average of 8 insect parts in a chocolate bar.  more...

August 1 ,  1790 :  The first US Census was completed.  more...

A camshaft is a rotating cylindrical shaft used to regulate the injection of vaporized fuel in an internal combustion engine. These are occasionally confused with the crankshaft of the engine, where the reciprocating motion of the pistons is converted into rotational energy. Instead, camshafts are responsible for the accurately-timed fuel injections required by internal combustion engines. Camshafts have multiple cams on them, which are used to open valves through either direct contact or pushrods. A camshaft is directly coupled to the crankshaft, so that the valve openings are timed accordingly.

Camshafts can be found in many different types of machines that require mechanical timing. Most of the time, they are found in internal combustion engines and perform the essential task of timing fuel injection. Even though camshafts can be found in different types of machines, they are typically used for valve-timing purposes. An example of this would be a fuel burner which injects fuel in timed intervals to help reduce fuel consumption. Camshafts have also played a role in older machines, such as water pumps and mechanical clocks.

An engine camshaft can be made from many different types of materials. The materials used in the camshaft depend upon the quality and type of engine being manufactured. For most mass-produced automobiles, chilled cast iron is used. Not only is it cheap, but chilled cast iron is also extremely durable and reliable. This is because cold treating increases the strength and hardness of any metal that undergoes the process.

Ad

For higher-quality camshafts, billet steel is used. While far superior to chilled cast iron in performance, the manufacturing process is both laborious and expensive— thus, billet steel is seldom found outside of high-performance or luxury cars. Camshafts made from this material are often made through the use of computerized numerical control (CNC) machines to ensure precision.

Camshaft timing is incredibly important for internal combustion engine performance. The rotation of the camshaft opens both the intake and exhaust valves of the cylinder, so proper timing is necessary for making sure fuel is injected and exhausted at the correct times. Since the camshaft is often coupled directly to the crankshaft itself, it can be timed in accordance with the position of the crankshaft. The two shafts are coupled through either a belt or gear arrangement, depending on the location of the camshaft.

The location of the camshaft can vary and depends on whether or not the cams—or lobes—of the shaft come in direct contact with the valves or open the valves through pushrods. Ideally, it will be positioned directly above the cylinder head, which eliminates the need for pushrods. For this reason, many internal combustion engines have camshafts located directly above the cylinder heads.

Ad

Discuss this Article

appu
Post 3

I'd like to suggest some more materials for camshaft other than chilled cast iron and billet steel: forged steel, gray cast iron or nickel steel.

appu
Post 2

I just want to know, other than chilled cast iron and billet steel, which other materials can be used for camshaft which are equally good?

Talentryto
Post 1

This article brought back good memories of hanging out in my grandfather's garage. When he would be repairing cars, he would let me hang out and show me all of the different car parts and they work together to make the vehicle run. Car engines seem much more complicated and computerized today than they were back then!

Post your comments

Post Anonymously

Login

username
password
forgot password?

Register

username
password
confirm
email