Drive Rollers and Idler Rollers Information
Drive rollers and idler rollers are cylindrically-shaped material handling components that convey items through a machine, process, or environment. They deliver time, space, and energy efficiencies in resource handling applications.
Drive rollers rotate via direct interaction with a motor. Internal electric motors power motorized drive rollers (MDR). Belt-driven drive rollers receive rotational energy from linked motors. Idler rollers do not receive direct mechanical input from a power source, though they may be linked into a tranmission via belts or contact with other moving parts. Idler rollers also maintain or adjust tension in a transmission. They are effective for supporting conveyed materials between drive rollers and are the sole roller type in gravity conveyors.
These components support conveyor belts and control the flow of materials. They can also be situated adjacently to eliminate the use of a conveyor belt, provided the materials being conveyed have surfaces or form factors suitable for this. Drive and idler rollers can also be used to process thin substrates, such as in a printer. Uniquely-shaped roller structures are capable of steering the direction of motion of a load on a belt or handling unusual materials.
Electric-powered, electronically-controlled drive rollers have replaced lineshaft units. Lineshaft devices require power transmitted from a central source. Early energy sources included water wheels and steam and diesel engines where the motor transmitted power via a belt, also called a lineshaft. This created constraints in the conveyor construction and placement of cylinders. As a result, the setups suffered mechanical efficiency losses given the distance from the power source.
Over the course of time, compact motors placed along a production line gained increased acceptance in lieu of lineshaft systems. The change enabled the configuration of assembly lines around industrial processes and the areas in which they were operating. This led to enhanced operational efficiency, with material transfer consuming less time and energy. Integration of modern technology in conveyor setups facilitated the introduction of space-saving solutions.
Roller units support numerous options, including:
- MDRs feature an internal electric motor housed in the load-bearing cylinder. MDRs deliver precision control over product movement and superior energy efficiency over a broad range of capacities. A belt can allocate power to adjacent rollers, with one masted MDR driving multiple units.
- Belt-driven drive rollers move resources with increased speed and minimum energy consumption.
- Conveyor rollers guide conveyor belts and support the carried masses.
- Rubber-coated rollers possess a diverse set of attributes, making them suited for handling items at high temperatures, with exposure to oil, water, or corrosive chemicals.
- Impact idlers are coated with high-strength, shock-absorbing materials. The roller cores and coating minimize structural deformation from weight transfer shocks.
- Troughing idlers guide the transportation of objects on a conveyor. Idler rollers running beneath a conveyor belt form a trough that keeps loose material from falling off the belt.
Idler pulleys guide the rotation of belts in a conveying system and maintain or alter the tension in the belt.
Roller bearings are essential to drive and idler roller roller function. They minimize energy losses due to mechanical friction for a set range of load and speed handling characteristics. The surface of rollers are often coated or altered to improve performance parameters. Rubber-based coatings alter the friction, shock absorption, noise reduction, and deformation properties. Special coatings enable resistance to corrosion, mechanical wear, and temperature variations. Bulky resources found in logistics, mining, and ore processing deploy heavy duty rubber-coated elements. These items absorb impact, reduce noise, and dampen vibration.
Non-uniform shaped structures are capable of steering the direction of motion of the load on a belt. The troughed design supports the system by means of rollers positioned at inclined angles, creating troughs to prevent material spillage.
Standard products comprise of diverse materials based on functional requirements, including:
- Steel cores are integrated into units with amplified load-bearing capacity, such as pallet conveyors.
- Aluminum devices designed to cover lowest inertial ratings are suitable for precision and rapid transfer.
- Zinc- and aluminum-coated surfaces are not susceptible to rust.
- Neoprene offers resistance to weathering and petroleum-based fluids and is flame retarding.
- EPDM (ethylene propylene diene monomer) is resistant to chemicals other than petroleum-based substances.
- Buna-N (nitrile-butadiene) possesses resistance to petroleum-based fluids.
- Silicone withstands severe temperature environments.
- HNBR (hydrogenated nitrile) is unaffected by heat, oil, fuel, and ozone.
- Urethane is impervious to solvents and abrasion.
Considerations when selecting drive and idler rollers are broadly.
- Weight and physical shape of the load
- The device dimensions and maximum bearing capacity
- Desired speed for loading, transporting, and feeding an object on the rollers
- Operational temperature of the environment
- Exposure to water, natural oils, ozone, and petroleum-based fluids
- Expected levels of surface abrasion and wear
Drive rollers are assembled in automated modular units. These platforms feature control systems on several linked modules that authorize selective control over units in the assembly environment. A modular configuration employing sensors offers superior performance. The sensors activate the drive motors only when a load is detected, thus eliminating the need for continual operation of the setup.
Drive and idler rollers cover a myriad of current and potential functions in multiple industries where, including:
- Aerospace parts and assembly
- Agricultural equipment
- Consumer goods manufacturing
- Food production
- Medical equipment
- Logistics and package handling
- Printing and presses
Drive and idler rollers are subject to a selection of standards, including:
NPFC - A-A-59955 - Conveyor, roller, gravity, dock, high-line, conveyorized
ASTM B633 - Specifications for electrodeposited coatings of zinc on iron and steel
ISO 606 - Short-pitch transmission precision roller and bush chains, attachments and associated chain sprockets