Something Abount External Nut Linear Actuator

The most popular design of linear actuators, the external nut configuration is simple, compact, and offers a high level of design flexibility. In the external nut configuration, the shaft of the stepper motor is replaced with a lead screw. In a typical application, the motor is fixed in position and an apparatus is attached to the nut. As the lead screw rotates, the external nut travels along the length of the screw, providing linear motion.

The length and the pitch of the lead screw of linear actuator are highly customizable, making the external nut configuration useful for a wide variety of applications. Numerous mounting options paired with the many types of nuts available help tailor this particular linear actuator to best fit a user’s specific situation. In addition, the external nut configuration helps achieve greater acceleration and maximum speeds than other configurations while also offering greater efficiency in terms of power consumption.

Something Abount External Nut Linear Actuator


There are a few limitations to consider that could make the use of the external nut linear actuator configuration challenging within certain applications. The length of a lead screw in this particular configuration, for example, is limited. If the end of the screw is unsupported within an application, you run the risk of experiencing flex. The longer the lead screw is, in other words, the more flex it will have. Additionally, as the screw rotates, you may experience vibration. This is especially true at higher speeds. Excessive vibration can contribute to lower accuracy and increased noise generation as well as a whole host of other problems.

The maximum force this application can handle is also limited, meaning that you should carefully consider how much strength you’ll need before selecting the external nut configuration.

How to Choose the Right Linear Actuator for Your CNC Project

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