TIAGO

BRAKES

INTRODUCTION

This brake is designed for use on rear wheels and

is equally efficient in both directions of rotation. A

mechanical lever mechanism is incorporated for

normal hand brake operation. The feature of this

brake is the automatic adjustment of the brake

shoes takes place when the foot brake is applied.

The leading and trailing shoes are connected at

one end by a twin-piston wheel cylinder and an

adjuster assembly. The adjuster assembly

consists of a male and female push rod with an

adjuster nut operated by a pawl.

Coupled on the trailing shoe is a hand brake

lever, which pivots on a pin at the wheel cylinder

end of the shoe.

A spring dowel fitted at the leading shoe provides

a pivot for the pawl, which is restrained in position

by a spring attached in the web. The hand brake

cable passes through a hole in the back plate

assembly (6), and the nipple fits in the end of the

hand brake lever. When the hand brake is

applied, the cable pulls the lever and this

movement is transferred via the adjuster

assembly (4) to the shoes, which move outwards

onto the drum.

When the foot brake is operated, both the shoes

are pushed on to the drum by the wheel cylinder

plunger. As the shoe linings wear, the outward

movement of the shoes exceeds a predetermined

amount and the pawl pivots on the spring dowel to

rotate the serrated nut. This action lengthens the

adjuster assembly sufficiently to reduce the

clearance between the brake shoes and drum to

the desired minimum. The adjustment is repeated,

whenever necessary, according to the rate of

lining wear.