An Automatic Brake Adjuster
Page 77
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A Simple Device which Replaces Existing Brakecamshaft Levers KNOWN as the Safety Brake Regulator is a device marketed by Brown Bros., Ltd., Brown Buildings, Great Eastern Street, London, E.C.2. It takes the form of a simple mechanism attached to the brake cam shaft. It replaces an existing camshaft lever, or, in a set of brakes of the compensated type, it can be nrunted so that one controls the brakes on the front wheels and the other those on the rear wheels.
The principal part of the device is a housing which acts as the case for the moving components and which serves as the lever coupled to the brake-operating rod; this housing carries a pawl and spring. On the brake camshaft is carried a ratchet wheel, the hub of which is keyed to the shaft. The pawl in the housing engages with this ratchet wheel and forms the connection between the two, so that when the Pedal is depressed the lever is pulled forward and rotates the ratchet wheel, , which, in turn, applies the brake.
When the pedal is released the housing naturally moves back and the brake pull-off springs tend also to rotate the ratchet wheel. Another pawl, however, carried on tl lever coupled to the axle casing, comes into operation and ensures that the ratchet wheel rotates backward only so far as is necessary to give the requisite clearance for the brake shoes.
As the facings wear the ratchet wheel will not revolve so far when the pedal is released because another tooth will have 'passed the stationary pawl. In this way, the pawl in the 'housing merely acts as a one-way coupling, whilst the stationary pawl automatically adjusts the brakes hy taking up
lost motion. The price is £1 Sc. each, £2 10s. per pair, or f5 per set of four. Fitting is a simple matter. as all that is necessary is the removal of the old brakecamshaft levers. Once in position the pedal is applied and the S.B.R. takes up any lost motion and sets itself for
further service, without additional attention, until the facings are worn out.
One of the main advantages of this device is, of .conrse, that it obviates the need for periodical adjustment of the brakes during the useful life of a set of facings. In mountainous districts, where prolonged periods of brake application are necessary, use of the S.B.R. ensures that the shoes are kept in correct adjustment without the need for checking en route. Ottviously it will save much labour, when non-comperfsated brakes are employed; there will be no need to jack up the wheels and test by pulling
around each wheel in turn. • The S.B.R. is easily installed, and the length of the arm, between the end of the pendant lever and the clip around the axle casing, is adjustable.