A brake element for use in applying a frictional braking force to a rotating brake rotor includes a backing plate and a pad of friction material mounted on the backing plate.

The braking subassembly (4) comprises an adjustable screw (6), a spring (7) and a braking sheet (8).

The mechanical braking device composed of the adjustable screw (6), the spring (7) and the braking sheet (8) has the advantages of a simple and compact structure, low cost and high braking performance.

As a result of the rotation of the first trigger lever (28), a pawl (32) releases a crossbar (27), whereupon pressure springs (22) press a released braking plate (18) against a cable strand (3) and bring the cable strand (3) to a halt.

Thus the friction between the braking sheet (8) and the outer sleeve (5) of the rotating shaft is varied.

The backing plate is formed with an integral wear sensor portion in the form of a punched tab feature that is bent out of the mounting plate.

It is arranged sideways outside the rolling device and comprises a braking plate (7) which extends at least on the periphery of the wheel above the plate.

The bottom surface of the braking sheet (8) is tightly stuck to the outside surface of the outer sleeve (5) of the rotating shaft.

The rear portion (6b) of the brake plate and sheet cut-off plate has part of its lower surface held in permanent contact with the outer peripheral surface of the sheet roll.

Air pressure in the low pressure container (11) is below the air pressure of ambient air in the braking plate's rest position.

When the adjustable screw (6) is adjusted and the amount of the spring (7) comprssion is changed, the pressure from the spring (7) to the braking sheet (8) is varied correspondingly.