Ball and lead screw assemblies consist of three main components: the screw shaft, the ball nut, and the end support bearings. More than just an accessory, end support bearings have a significant influence on the rigidity, maximum speed and buckling load of screw assemblies. There are two primary types of support that can be implemented for […]
Ball + lead + roller screws
Examining screws from three different angles
The thread design of a power transmission screw—whether a lead screw or a ball screw—plays a critical role in the screw’s function. Aside from the basic thread form (acme, trapezoidal, etc.), the three main aspects of the thread geometry—helix angle, lead angle, and thread angle—help to distinguish different types of screws from each other and play […]
How to calculate motor drive torque for ball screws
When sizing a motor, one of the most important factors is the required torque. In general, motor torque-speed curves outline two primary areas of permissible torque: continuous and intermittent. Intermittent motor torque is allowed only for a short time (specified by the manufacturer) and in most cases is the torque required during acceleration. A motor’s […]
Designing (seventh-axis) linear motion tracks for robotic positioning
By Lisa Eitel • Robot-positioning tracks can add flexibility to manufacturing spaces, but must be fast, accurate, and safe to be truly useful. Here we take a look at drives that deliver. Robot positioning systems are long tracks in warehouse, aerospace, and automotive facilities to let one robot perform multiple tasks. Also called robot-transfer units or […]
Ground vs. Rolled Ball Screws: Does manufacturing method matter?
There’s much debate among manufacturers, and sometimes among users, regarding the superiority (or lack thereof) of ball screws with ground threads over those with threads that are formed by rolling. Ground ball screws have traditionally been the choice for high-precision applications, whereas rolled screws offered an economical solution for general industrial and automation applications. But […]
What does “lubricated for life” mean?
Lubrication is one of the most critical factors contributing to linear bearing life, and to achieve optimum performance users historically had to ensure that a lubrication routine was included in their operating and maintenance program, or implement an automated lubrication system. Seeing the opportunity to reduce maintenance and improve total cost of ownership, linear bearing […]
Tips for preventing linear bearing corrosion
Corrosive environments can include anything from detergents and chemicals for washdown (the high-pressure cleaning of equipment), to acid baths and their related vapors, to chemicals in food processing. Because profiled linear rails, round shafts, and ball screws are made primarily from steel components, they’re highly susceptible to corrosive agents, which can quickly cause rust, pitting, […]
New electric cylinder for the food industry
PHD is has released the PHD Plus Series ECP Electric IP69K Cylinder. Series ECP Electric IP69K Cylinders are designed for food processing and packaging equipment used in high pressure/high temperature washdown and clean-in-place (CIP) environments. These performance electric cylinders are available in either ball screw or lead screw (polymer nut) versions, providing a wide range […]
igus lightweight leadscrew options offer up to 60% weight savings
Featuring tribologically optimized plastic leadscrew nuts and hard anodized aluminum screws, new dryspin leadscrew options offer considerable weight savings, as well as the reduction of required maintenance and external lubrication, with increases in service life due. A range of leadscrew diameters are available, ranging from 6 to 20 mm. Using asymmetric geometry to reduce friction, […]
How to calculate mean equivalent dynamic load
It’s rare in linear motion for a guide or ball screw to carry the same load throughout its move cycle. Even in simple pick-and-place applications, the load will be higher in one direction (the pick and carry phase) than in the other direction (the place and return phase). But even more common is for a […]