Mechanical Design Handbook

Machine designers have to deal with several number of equations in their design projects. There are a number of ways to solve for roots of algebraic and transcendental equations. Sometimes, the roots could be obtained by direct methods. However, there are many more that could not. The classical equation such as f(x) = e -x - x cannot be solved analytically. For this case, the only alternative is an approximate solution technique. There are several methods available to solve the root finding problem such as " bracketing methods " and " Open methods ". The bracketing methods require 2 initial guesses for the root. These guesses must "bracket" the root. The numerical methods using bracketing methods consist of the following techniques: The Bisection Method : The idea of this technique is incremental search that related to the sign change. Sometimes, this technique is called binary chopping , or Bolzano's method . The False-Position Method : It's the ...

N umerical methods can be very helpful for calculation of mechanical engineering design. What I would like to introduce in this post is about calculation of the first derivative using numerical methods in Microsoft Excel without using any math software . From the textbook, there are a lot of formula and explanation about how we get this formula. So I would skip that part and directly start with the selected formula as an example. We know that the first derivative of function f(x) can be calculated from the following equation It is the formula to calculate first derivative using interior points that give the error of h 4 That means we will use the values of function at other 4 points around the center of interest to calculate the first derivative and the smaller the step size (h), the higher accuracy of calculation result. The following is the equation of favorite cam curve - Cycloid The cam follower will slowly move at the beginning of time and start accelerating, then decelerating i...

Normally we can find a lot of ball joints with pull rod at every machine. It is used to transmit power from a lever to another link in cam or even pneumatic driven mechanism. It's the part of the system that we can adjust its length due to imperfection in manufacturing of machine parts. For example, we may require high accuracy of mechanism at one position but we cannot achieve it with the fixed length of rod, therefore the use of adjusting rod like this is required. This adjusting rod consists of right-handed ball joint at one side and left-handed ball joint at another side. This is because we need to adjust the distance between center of both ball joints by turning the pull rod then the screw threads will increase or decrease the distance depending on the turning direction of the pull rod. Of course, if we use right-handed ball joints at both sides, there will be no length changes from turning of the pull rod, but sliding of the pull rod to one side! Normally, the coarse thread...

As the designation implies, tool steels serve primarily for making tools used in manufacturing and in the trades for the working and forming of metals, wood, plastics, and other industrial materials. Tools must withstand high specific loads, often concentrated at exposed areas, may have to operate at elevated or rapidly changing temperatures and in continual contact with abrasive types of work materials, and are often subjected to shocks, or may have to perform under other varieties of adverse conditions. Nevertheless, when employed under circumstances that are regarded as normal operating conditions, the tool should not suffer major damage, untimely wear resulting in the dulling of the edges, or be susceptible to detrimental metallurgical changes. Tools for less demanding uses, such as ordinary handtools, including hammers, chisels, files, mining bits, etc., are often made of standard AISI steels that are not considered as belonging to any of the tool steel categories. The steel for m...

Needle Roller Cam Followers Needle Roller Cam Followers have a heavy outer ring cross section and a full complement of needle rollers. They offer high dynamic and static load carrying capability, and anti-friction performance, in a compact design. They are used as track rollers, cam followers, and in a wide range of linear motion systems. Standard Stud cam followers offer the mounting convenience of a threaded stud and are designed to accommodate moderate loads. They are available with and without seals. Standard stud cam followers are also available with crowned outer rings for applications where misalignment is a problem. Heavy Stud cam followers are designed to provide additional stud strength for applications with high loading or shock loads. Heavy stud cam followers are available with and without seals, and with crowned outer rings. Yoke Type cam followers are intended primarily for applications where loading conditions exceed the capabilities of stud type cam followe...