How to Choose the Right Linear Actuator to Boost Performance
It can be difficult to choose the right linear actuator, and choosing the incorrect one could significantly impair your application's efficiency and limit its lifespan. Discover the various linear actuator types. How to choose the best one. And what services can assist make the choice as easy as 1-2-3!
When accurate rotary motion is required, step motors are employed. On the other hand, step motor-driven linear actuators are utilized in applications requiring precise linear motion. In essence, a lead screw and nut are used to convert the precise rotational motion that a step motor produces into linear motion.
When choosing a linear actuator, there are a few distinct designs to take into account. Your creation each design serves a different function and has pros and cons, so let's look at each one individually:
Outside nut
The external nut configuration, the most common design for linear actuators. It is straightforward, small, and provides a high degree of design flexibility. In the external nut design, a lead screw is used in place of the stepper motor's shaft. In a typical application, a device is fastened to the nut and the motor is fixed in place. The external nut moves linearly along the lead screw's length as it turns, supplying motion.
The lead screw's length and pitch can be adjusted to fit a wide range of applications. Which makes the external nut arrangement effective. Numerous mounting possibilities combined with the this specific linear actuator can be customized. Using a variety of nuts to match a user's unique circumstances. Additionally, compared to previous setups, the external nut arrangement offers improved power consumption efficiency. While also enabling faster acceleration and top speeds.
Restriction in account
There are a few restrictions to take into account that can make using the external nut configuration in some applications difficult. For instance, the length of a lead linear actuators screw in this particular setup is constrained. Flex is a possibility if the screw's end is not supported within the application. In other words, the lead screw will have greater flex the longer it is. You might feel a vibration while the screw rotates as well. Particularly, this is true at faster rates.
Non-captive
The nut is integrated into the motor's rotor in a non-captive design. The lead screw is threaded into the shaft of the rotor, which generates linear motion as it revolves. Your device can be connected either directly to the motor or the lead screw in this situation.
The lead screw is often fixed in the rotation when the device is fastened directly to the motor. The lead screw's length is traversed by the actuators motor as the rotor turns, causing linear motion. The maximum length of the lead screw can be longer than that of an actuator with an external nut since both ends of the lead screw are supported. For uses requiring longer travel, this is a common choice. This arrangement can more force than an exterior nut design can withstand.
Less vibration in actuator
The motor offers more mass and, as a result, more damping power, which is another benefit to take into account. You will therefore feel less vibration, which frequently translates into quieter and more precise action. When a rotating lead screw can potentially clash with other parts or prove dangerous, a non-captive design may also be preferable. Less moving parts are exposed because the lead screw is fixed.
The need for additional space is this design's major drawback. The motor leads require additional room since they frequently need to be directed and because they typically have a wider diameter than, say. A straightforward nut with a flange. The leads in question frequently must move with the motor and are much longer than in other configurations.
