About carrier roller / Belt conveyor -16

About carrier roller

A side which is used to convey object in a belt conveyor is called carrier side. In side view of main body of a conveyor, a conveyor shapes an oval shape which is long in horizontally and pulleys (rollers) are attached at its both ends. Upper side which is used to carry objects is called carrier side. Rollers that hold conveyor belt at the carrier side is called carrier rollers.
When large conveyance capacity and strength are required for black rubber belt conveyor, we normally don’t use ready-made conveyor belt but build-to-order (BTO) belts. For conveyance of large amounts of objects, conveyor belt is made to be ship bottom shape (＼＿／), but not flat. The ship bottom shape is made at conveying side, in other words carrier side.
In the first place, there are mainly two kinds of rollers. Rollers holding conveyor belt at transporting side are called carrier roller and roller holding belt at returning side are called return rollers.
Ship bottom shape of conveyor belt is made at transporting side (carrier side in other words) and the ship bottom shape is made with either three rollers or two rollers. These rollers are put into a holder specially made for them and hold conveyor belt together with the holder. It is called “3 point carrier roller” when 3 rollers are used, and “2 point carrier rollers” when 2 rollers are used. “3 point carrier roller” is commonly used in build-to-order conveyors and “2 point carrier roller” is used in ready-made conveyors.
There are standardized dimensions for the “carrier roller” and “return roller” in JIS (Japan Industrial Standard). These dimensions are used for most of build-to-order belt conveyor with ship bottom shape. However, none-JIS but manufacturer’s own specification is often used for rollers in ready-made belt conveyor, and the diameter of rollers are normally smaller than ones that JIS standardizes. It is probably because manufacturer tend to reduce production cost as much as possible.
It can be said that rollers which is in compliance with JIS outwears others.

The following is a picture of hanging-typed 3 point carrier roller.