In order for a motor to accelerate or decelerate a load, it must overcome the load’s inertia, or resistance to change in motion, as explained in Newton’s First Law. In belt-driven linear motion systems, the motor has to overcome not only the inertia of the applied load, but also the inertia of the belt, pulleys, […]
Applications
Motion basics: What is ball conformity in linear guides and screws?
In linear guides and ball screws, load-carrying balls or rollers can ride on planar (flat) raceways, as with non-recirculating linear roller bearings, or in curved raceways, as with ball screws and profiled rail guides. When a ball or roller rides on a planar raceway, the contact between the rolling element and the raceway will be […]
Mechanical properties of materials: Hardness
Hardness is a common specification for linear shafts and guides — especially those used with ball and roller bearings, where the guide encounters extremely high loads over very small areas. The hardness of a bearing surface can significantly affect the life of the system and is often accounted for by applying a hardness correction factor […]
A guide to stainless steels for linear motion components
For applications that involve corrosive environments, designers of linear motion systems can take precautions such as using covers to protect vulnerable components, ordering parts with special coatings or platings, and strategically placing sensitive components within the machine or system to minimize their exposure to hazardous liquids or fumes. But some applications — due to the nature […]
What are some linear motion options for moving multiple loads independently?
From a mechanical standpoint, one of the more challenging applications in linear motion has traditionally been to move two or more loads independently, as is required in some handling, transport, and inspection applications. While using multiple linear systems, or preassembled actuators, is a simple solution mechanically, this option typically requires a significant amount of space […]
How to account for ball and lead screw inertia during system design
When sizing a motion system with a ball or lead screw drive, the first step is to determine the screw diameter and lead that can meet the application requirements for thrust force, speed, and compressive (buckling) loads. Once the screw diameter and lead are determined, the next step is to choose a motor that can […]
What’s the difference between moment and torque in linear motion applications?
In linear motion, we often deal with applications that involve forces applied at a distance from a linear guide — referred to as cantilevered, or moment, loads. In these cases, we’re concerned with guide’s moment load capacity, or its ability to resist rotating. But we also deal with components that should rotate when a force […]
Smart mechatronics add capabilities to linear motion applications
Today’s manufacturing system OEMs and automation end users are constantly seeking technology advancements to help make their lives easier. Industry 4.0 innovations have spurred a new class of smart technologies that combine digital electronics and communication interfaces for more sophistication, functionality, and ease of use. By Richard Hansen • Senior automation engineer | Bosch Rexroth […]
What is ball screw whip and why does it happen?
Ball screws are often the drive mechanism of choice in applications that require high thrust forces with excellent positioning accuracy and repeatability. But one of the drawbacks of ball screw technology is that speed is inversely related to length — the longer the ball screw shaft, the more likely it is to whip, like a […]
White paper guides semiconductor manufacturing machinery OEMs to prevent fab failures
A new white paper seeks to prevent fab failures before they start by detailing critical linear motion guidance for semiconductor manufacturing machinery OEMs and fab engineers. Reliable linear motion is an absolute operational necessity in a semiconductor fab. From a prevention standpoint, semiconductor manufacturing machinery OEMs must monitor even relatively rare failure risks in linear […]
