CHAIN ROLLER BEARINGS.
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THE DEMANDS which are being made in the motor engineering trade on the, carrying capacity and reliability of bearings has led to the substitution of roller bearings for ball bearings in certain places where the loads would be excessive for the hitter type. Unfortunately, up to the present, roller bearings have suffered somewhat because they are not quite so 'frictionless as are
ball .bearings. This has been, chiefly because of the rollers rubbing against each other or against the cages which separate them.
An interesting type of roller bearing hat been introduced, and is now being manufactured, by the Lancashire Ordnance-Accessories Co.., Ltd., of Stock,. port. This type of bearing is known as theC.R.B., an abbreviation of chain roller bearing.
The principal feature of the bearing is the employment td an endless and detachable chain as a means for seParating and guiding the rollers. As the "latter can be spaced very closely together, the maxi. mum number and largest possible diameter rollers can be employed in each bearing. Each roller is hollow, and through it passes a chain link pin. The diameter of the hole in each roller is small, and, being near the axis, the rubbing speed is small, and thus very little wear occurs on the pin. Being hollow, the rollers are given a certain, though very, slight, amount of elasticity, and under heavy loads: the rollers may deflect an infinitesimal amount, but sufficient to -cause.the load to be distributed. over •a large number of rollers.
The experience of the manufacturers has provud that the hollow roller is less liable to initial stresses set up during the hardening pi.ocessesr than is the solid roller.
Each chain has a detachable link with a..spring fastening clip, which allows the chain to be unwrapped from the inner race for inspectioh, cleaning, or replacement. Tins is of particular advantage when the bearings are required for use with -crankshafts, as in this case the inner races may be dispensed with, -and the chain with its rollers wrapped over and fastened round the crankshaft itself, provided that the diameter of this is made the same as the standard inner r^ce. . Thus the difficulty of threadlnx, the inner race or rigid cage over the crank webs is obviated, and creeping eliminated. It should be understood that the chain roller bearing is designed to take radial lords only, and where alarge amount of end thrust occurs, it should be taken up by means of ball thrust waShers, or by plain hardened steel washers where the thrust is slight.
Bearings of this type have been running continuously for a long period under tests of the utmost severity, and have given completely successful results. " C.R.B. beatings will be manufactured to the same standard overall sizes, both inch and metric, as have already been established throughout the, -world.