Idler Sprockets - Single Bearing, Double Bearing

Brand :

MISUMI

Caution

Product Description

Sprockets with built-in bearings.
See here for tension units that use this product.

[ ! ] The bearing is located at the center of the sprocket.

Single Bearing
DRC
DRCS
(Stainless Steel)

Double Bearings
DRCW

Type		[M] Material		[S] Surface Treatment
Single Bearing	Double Bearings	Main Body	Bearing	[S] Surface Treatment
DRC	DRCW	S35C Equivalent (Induction Hardened Teeth Tip)	Steel	Black oxide
DRCS	—	Stainless Steel	Stainless Steel	—

Specifications/Overview

■Features of Double Bearing Type (DRCW)

Since double bearings are installed, this type of idler sprocket can withstand heavier load than the Single Type can and is suitable for adjusting tension on the driven side.

■When Using Idlers

Chain elongation decreases transmission efficiency and accelerates wear, resulting in short life.
Adjustment mechanism is required for the following power transmission conditions.

1. The center distance between shafts is long.
(In the case that the shaft center distance exceeds 30 to 50 times greater than used chain pitch, or 20 times or greater than chain pitch under pulsating loads.)
2. Both axis positions are vertical or close to it.
3. The distance between both shaft centers is short, and the upper side is the chain's loose side.
4. The overall chain length is long with a multi-shaft transmission.
5. When the chain is severely vibrating.
There are 2 ways to adjust for the stretch of the chain.

1. Installing an idler or a tensioner (When (1) the both sprocket shaft centers are fixed; (2) transmission is in vertical direction; or (3) the chain causes vibration)
2. Moving either of the shafts (This may be the easiest way for regular transmission applications.)

(1) When both sprocket shaft centers are fixed

(2) Vertical Transmission

(3) When the chain causes vibration

Rollers or guide rails are used as idlers in very low speed operations while Sprockets are commonly used for power transmitting chains. The idler should be installed on the chain's loose side span rather than on the tense side, except otherwise needed or in applications that require reversing operation. Installing the idler on the tension side unnecessarily increases the chain tension and makes its service life shorter. Ensure that the number of idler teeth does not exceed the maximum rotational speed (note when the number of teeth is less than the small sprocket, the rotational speed increases). At least 3 idler teeth should contact with chain. There are several ways of idler adjustment: 1. Eccentric shaft system, 2. Arm system, 3. Sliding system.