SUSPENSION TO ORDER.
IT has been recognised for a long time that friction shock-absorbers cannot successfully cope with conditions as varied as slow driving on rough surfaces, fast road work and everyday use in towns, not to speak of the variation in load caused by the addition of two rear passengers or a full load of petrol on a light car. In spite of this, the majority of drivers do not trouble to adjust the pressure of the clamping nuts, and so their cars are either bumped about on bad surfaces or unstable on corners according to the permanent setting at which they are set. This difficulty was first overcome on the Andre Telecontrol system, in which cables controlled from hand-wheels on the dash tightened or relieved the pressure of the clamping bolts. This type was superseded by the Hydro-Telecontrol layout, in which small brake-shoes mounted on one arm of the shock-absorber operate on the inner surface of a drum fixed to the other, Fluid forced through pipes from a regulator under the dash expands a
rubber bag which lies between the brakeshoes, allowing the friction to be varied. Pressure between the shock-absorbers is equalised, and a pressure-guage allows a predetermined setting to be repeated at will.
A great number of these sets have been. installed and function perfectly, but experience has Shown points which could be improved. The piston in the regulator,. which sometimes leaked if it had been left slacked off for a long period has been replaced by a sealed flexible diaphragm, and this exerts pressure on the fluid. when compressed by the movement of the screwed control rod.
No leak can therefore occur at this. point. At the other end the rubber bag,, which formerly consisted of two halves cemented together is now constructed out of one piece of moulded rubber, the core being left inside.
The shock-absorbers and regulators are supplied filled with fluid, and sealed, and. the pressure pipes are fitted with unions. threaded to take a hand-pump adaptor. With the aid of this the pipes can be fully charged with the fluid without difficulty,. overcoming any trouble which might otherwise occur through air being trapped in any part of the installation.
