Tag Archives: Friction

What are Miniature Slide Guides?

Slide guides are industrial mechanical guides to reduce friction in linear motions. They use rolling elements, either hardened steel rollers or balls, moving along two raceways, with a stick-slip arrangement. This provides a smooth linear motion in either direction even when the load is heavy. Usually, slide guides carry their loads on one or more blocks or carriages riding on a rail. Instead of carrying loads, they can also guide other components, making sure they move smoothly and easily along the rail. The rail length depending on the required length of the application is usually made up of several straight sections. For some slide guides, the linear motion can be unlimited in distance, as the rolling elements travel in recirculating paths.

Since the guides are not powered, they cannot provide the drive to move the load. The force to move the load actually comes from a mechanism such as a linear actuator, lead screw, ball screw, or a belt-and-pulley arrangement. A limit switch or some other form of brake outfitted on the linear drive is necessary to stop the motion on a slide guide. Users may also use other stopping mechanisms such as end stoppers or a bumper pad may also be used to halt the motion.

Applications where the space and weight are both limited use miniature slide guides. Although these offer the same functionality and have the same form, miniature slide guides are limited to being only 25 mm in height, and 13 mm or less in width.

People call miniature slide guides with different names such as mini carriage on a profiled guide rail, or mini linear guides. Available in a range of sizes, the performance capabilities of mini slide guides scale with use.

For instance, a load carrying block may be as small as 6 X 12.9 mm, weigh as much as 0.8 gm., and ride on 100 mm rails carrying a load of 2.8 gm. The dynamic load rating for such small guides would be 0.21 kN.

On the other extreme, a block weighing 338 gm., with dimensions of 46 x 79.5 mm, may ride on 100 mm rails with a load of 209 gm. The dynamic load rating for such a large guide would be 12.4 kN. The top speed with which a mini slide guide typically moves is about 1.5 m per second.

Despite their compact size, mini slide guides direct their motion along a linear axis, much as their larger counterparts do. Their main advantage comes from the compact size, allowing them to be used in devices such as robots, medical devices, wafer-fabrication equipment, and hard-disc drives. The mini slide guides also use either balls or rollers as their friction reducing elements.

Mini slide guides use rolling ball elements made of stainless steel or carbon steel. They can support heavy loads and offer a long operational life. An all-stainless-steel construction is best suited for applications such as vacuum or clean rooms.

Mini slide guides that use roller or cylindrical elements offer lines of contact area rather than point contacts as balls do. This allows them to carry heavier loads than slide guides using rolling ball elements can.