What are Motorized Roller Conveyor Systems?

Modern powered roller conveyor systems use motorized rollers mounted within the conveyor frames. They’re compact in size, quiet and safe with 24 volt DC power. As a result, motorized rollers have become the dominant type of conveyor system in use today.
 
Warehouses and distribution centers rely on these conveyors for fast, smooth package movement. Importantly, sensors and controls ensure packages don’t get damaged by crushing against each other.

MDR conveyor system for robots

24V Motorized Roller Conveyors – MDR Overview

Motorized roller conveyors are a great choice for energy efficiency, low noise and easy maintenance. Use the abbreviation MDR (motorized driven roller) conveyors to refer to them.
MDR conveyors handle a multitude of products such as:
  • Packages
  • Tote Bins
  • Pallets
  • Tires
  • Cartons
  • Any product that will move on a roller conveyor

Ultimation is one of the leading manufacturers of motorized roller conveyor systems. We use the two leading brands; Itoh Denki is Japanese technology and Interroll is Swiss. In addition, all these motorized rollers are extremely compact and have outstanding durability.

Planning MDR Conveyor Projects

 
Firstly, powered roller conveyor using MDR rollers perform two functions:
  1. Moving the product from location ‘A’ to location ‘B’
  2. Providing buffering or accumulation of product
The two different material handling functions are very important when used together. Buffering means that if the conveyor is full or product, it will stop. But if the conveyor is empty, it will move forward. Secondly, to make best use of MDR technology, the total conveyor length is divided into zones.

Importantly, size each zone according to the largest product you are moving. Add about 3 – 18″ per zone for extra space. With at least one motorized roller per zone, MDR conveyor uses “zero pressure accumulation” (ZPA). In other words, ZPA basically means that the parts don’t crash into each other on the conveyor. Therefore loads continue moving along the MDR conveyor until they get close to (but do not touch) the product unit in front. Consequently there are no gaps in the assembly line. MDR conveyor systems have built in logic cards which automatically manage turning zones on and off. You can learn more about ZPA systems here.

Therefore, this reduces programming and commissioning time. Here’s more information on the motors used in a motorized roller conveyor. Please visit http://itohdenki.com/.  For Interroll conveyor technical motor information, you can visit https://www.interroll.com/.

MDR motorized conveyor roller motor
Cutaway of Itoh Denki 24V DC motorized conveyor roller

Motorized Conveyor Roller 90 degree pop-up transfer units

You can buy straight sections of MDR conveyor from Ultimation in ready to run modules. In addition, curves and 90 degree pop-up transfer units move the product around corners and merges.
 
Similarly, a 90 degree pop-up transfer system can move packages from one lane to another. Parts move into the transfer on the MDR rollers. After that, a second motor raises the load about 1-2″ up above the rollers on belts or chains. Finally, a third motor runs the belt or chains and the product moves off sideways.
MDR 90 Degree Pop Up Transfer

Why Use Motorized Roller Conveyors?

Older style conveyor systems used chains to link the rollers. However, powered roller conveyors save space by eliminating traditional power transmission components. For delivery applications multiple lines can be tiered up to take less vertical space. Above all, the quiet operation and space saving features make MDR conveyors very versatile.
Transportation and zero pressure accumulation are two typical applications of MDR. Therefore, with “Run only on Demand” feature, the rollers are off when no product is detected which results in saving energy. Larger Interroll conveyor motors are sometimes known as drum motors. Similarly, another term is roller drive motors. When used to control zones they provide zero pressure accumulation (ZPA) conveying.

Interroll and Itoh Denki Logos

Technical Specifications:

Depending upon the conveying application, different controls and accessories are available. Optional control cards make the MDR versatile for different accumulation activities. Load capacity can range from a few pounds to thousands of pounds per motorized zone. Finally, some typical Interroll conveyor specifications are shown below, with many more combinations available:

  • 15” – 60” between frame widths (i.e. the width of the conveyor)
  • Speeds ranging from 10 feet per minute (FPM) up to 200 FPM max speed. Please contact technical support for more information.
  • 24 VDC brushless motor or 120/240 V AC motors
  • Roller spacing 3” up to 6″ roller centers
  • Zero pressure accumulation with 18”, 24” or 30” or longer driven zones as part of a motorized roller conveyor
  • Variable speeds and reversible motion
  • Powder coat finishes and galvanized material available

MDR Power Transmission system choices:

  • No connection. In this setup, there are one or more motorized rollers. The other rollers are gravity (non-powered rollers). As an example, use this style where the conveyor is on a decline and you need low power transmission. Tire and wheel delivery conveyors use this system.
  • O-ring style belts. This is the most common system. For instance, the MDR rollers have two grooves. Connect these to adjacent gravity rollers (with grooves). The O-ring style belts are easy to install, and have a long life. They’re also very safe if personnel are nearby. Therefore, because MDR conveyors have small, distributed motors they are very safe. You can even stop them by hand!

Heavy Duty options:

  • Poly-V ribbed belts. Use these where you have heavier loads and need excellent power transmission. Poly-V belts are ribbed, and they connect to special caps on the end of the rollers. They achieve about 97% power transmission efficiency. As a consequence, Ultimation recommends placing the belts inside a finger guard to ensure safety.
  • Roller chain. The heaviest duty MDR systems use sprockets on the rollers and chains between rollers. They’re just like CDLR (Chain driven live roller) conveyors. But there is no separate electric motor as the MDR motor provides the torque. We use MDR sprocket rollers for pallet conveyor and truck tire and wheel conveyors. Importantly, some of these loads are up to 250 pounds per zone. It’s common to use 2.5″ diameter MDR motors with special internal gearing for these high loads.

MDR conveyors have some restrictions on environment applications:

  • Extreme Cold / Heat – Special models are available, but MDR motors are generally not suited for use in ovens
  • Corrosion resistance – Normal finish is galvanized. Stainless rollers and frames are available but very expensive
  • Food grade – Stainless available, but expensive. Dirt trapped in belts must be considered
  • Dirty conditions – special IP ratings with IP65 rated controllers available
  • Water resistance – available

Buy ready to ship modular 24V Powered Roller Conveyors Online

Ultimation builds ‘ready to ship’ modules of powered roller conveyors. There are available using both Interroll conveyor and Itoh Denki conveyor systems. We have various length, width, zone and roller spacing configurations, you can order these here. We also have 24V power supplies that are ready to install that you can buy online as well.

Finally, need help learning about other conveyor types, which types to use and how to specify them? This step by step guide will help.

Common Industries and Applications: