NEW VACUUM-SERVO SYSTEM
Page 48
If you've noticed an error in this article please click here to report it so we can fix it.
0 of our readers, Mr. F. L. Jones,
has submitted to us drawings and specifications in connection with a new type of vacuum-servo braking system, for which a provisional patent specification has been granted (No. 24,659/1930). This brake can be used for single vehicles or those towing trailers, also for the trailers themselves.
Special features in connection with the system are that if, while travelling, one or both coupling pipes to a trailer should fracture, the lorry brake is, by closing a tap, still available. The lorry brake is independent of that on the trailer, although controlled by the same tap. Even if the main suction pipe be broken, the lorry brake would have at least one emergency application in reserve, owing to the employment of a vacuum reservoir.
A gauge is used which informs the driver how much vacuum is available and it permits rapid testing of the pipes for leakage. These pipes have to withstand only atmospheric pressure ; therefore, the chance of failure in the pipe line is remote, but provision has been made to cope with this risk should it occur.
An important point is that the brakes can be applied should the vehicle run away on an incline,when the engine is stationary and the gear lever in neutral. The use of a reservoir permits several applications of the brakes after the engine has stopped, and, of course, the linkage is schemed to permit direct application by physical effort, irrespective of the servo mechanism.
Any of our readers who may be interested in this system should, in the first instance, apply to Messrs. A. M. and Wm. Clark, 53 and 54, Chancery Lane, London, W.C.2. An announcement regarding this patent occurs in the advertisement section of this issue, under the heading "Patents."