Chevrolet Cars.

Thames Star, Volume LXVI, Issue 19637, 19 February 1936, Page 6

Chevrolet Cars.

EFFECTIVE BRAKING. PRINCIPLE DESCRIBED. Ju chanjdnjr to hydraulic brakes on both chassis models, Chevrolet has adpated (his principle of brake actuation to its own design of brake mechanism within the brake drum. Instead oi' the cable operated floating cam formerly used at each wheel a master hydraulic cylinder with double opposed pistons is used to actuate each pair of one-piece articulated brake shoes. The master cylinder, whose piston is moved by the brake pedal to transmit pressure by a column of fluid to each of the wheel cylinders, is mounted on the frame. ,

The master piston is one inch in diameter, while wheel pistons are larger to give an increase of braking effect at the wheels. Front wheel pistons ai*e larger than those of the rear wheels, to balance the braking effect when, in stopping, extra weight thrown on the front wheels gives them greater traction. This arrangement prevents locking the rear wheels by themselves by heavy brake application.

The hand brake lever actuates both service brake shoes in both rear wheels. The connection is by flexible cable, connected to a lever and toggle mechanism within the rear brake drums.

On the de luxe models, brake drums arc of composite construction, comprising a cast-iron rim and a pressed steel web. The braking surface is accurately machined, after assembly to the wheel hub, assuring true concentricity. Long life, freedom from scoring, and more effective braking arc advantages claimed for cast-iron. The outer surface of the drum is machined in deep grooves that form live ribs, to promote cooling. On the lighter model, equally effective braking is obtained by using pressed steel drums, which are one inch larger in diameter than last year's, increasing the brake lining area to 158.! inches, 17 square inches more than formerly. An improved grade of closely grained steel is used for the drums, and their braking surfaces are machined to accurate form and smooth finish. Dirt shields have been added.