Linear motion devices and equipment are in all facets of day-to-day life. There are quite a number of them in the cars and trains you take to work or school and in virtually all the machines used to manufacture the complex objects around you.
Sliding windows and cabinets in your home are examples of everyday objects with simple linear motion components that use human power. More complex examples would be cars and dentist’s seats, and even more complex ones would be components used in the defense and aerospace industry, which may use an array of different sensors and automation to aid their function.
While broadly similar in their operating principles, there are thousands of differing linear motion components that could be bought off the shelf as well as infinite ways to design custom components. This variety is due to the different operating parameters these components are expected to perform in.
This means linear motion components have to be selected carefully, based on a set of important factors. Here are just a few of the important factors to consider when selecting these components.
This is how closely the linear motion components move within their intended positions. An amount of play is sometimes acceptable for some applications, but in critical applications, movements need to be much more accurate.
2.) Running parallelism
This refers to the deviation of the rails from the shafts. Better running parallelism means less friction, heat waste, and wear on the system.
Not to be confused with acceleration, this refers to the rate of movement of the components. In practice, this is meant to refer to the top speed, unless stated otherwise, such as in the case of linear motion devices with variable speeds.
4.) Acceleration and deceleration
This refers to the rate at which the speed of moving components changes. The rates should be appropriate for the function and not lead to system instability, premature wear, and unsafe operation.
5.) Load and moment
Different linear motion components are designed to take different loads from different axes. The pitch, roll, yaw, and other types of motion of the load relative to the components should be taken into account.
6.) Duty cycle
This refers to the number of reciprocating motions for a given amount of time. It can also be considered as the amount of time the mechanism is engaged compared to the total time in service.
7.) Cost and economy
The cost of different components can vary not only due to the materials and manufacturing processes involved, but also due to shipping, distribution, marketing expenses, regulatory costs, labor, and so on. This means that lower or higher costs may not necessarily reflect on the true functionality of components. Ideally, you want to choose the most affordable components that perform within your target parameters.
8.) Reliability and repeatability
This refers to how confident the users of a linear motion system can be that the movement will be predictable even after repeated use. Unreliable components may not always move in the same way when actuated, while reliable components can be reasonably expended to perform the same way between recommended maintenance periods and beyond.
The system must be able to resist permanent deformation in its intended use while having the right amount of flexibility as needed. This increases the linear motion component’s overall lifespan and helps prevent unsafe operation.
With so many factors to consider, mismatching motion control components and technologies are actually more common than one might expect, which can lead to a less than optimal service life and performance for different applications. By carefully considering the different factors in the context of the intended application, you can maximize your chances of selecting the right linear motion components.
Be sure to check out Misumi USA to find out more about linear motion components and their applications