199707 – Luber – Track Vacancy Detection Equipment Using Axle Counter

Block sections and station sections must be able to detect in one way or another, to be proven to be vacated prior to a subsequent movement.

This requirement is as old as Railways themselves, and is the fundamental requirements for the safe passage of trains. ‘The result of this is the continuous striving to improve this requirement through the development of elements which would improve the level of safety. During the past 80 to 90 years this process has developed in accordance with the change in mechanical and then electrical technological advances.

Track detection using track circuits is such a technical solution which if applied without separation, allows the initial design requirements to be fulfilled. ie. a clear track for the oncoming train.

For the simple reason that track circuits could not be used for tracks with steel sleepers, or for long tracks and are not economical for tracks with a poor track resistance or with continuously dirty rails, a technology what sought which was not restricted on its application. The result of this requirement a technique was developed which counted and registered the number of axles passing a particular point ie the so called track vacancy detection using axlecounters.

During the first phase one tried to count the axles with mechanical contacts and then register the number of axles via first a mechanical and later an electro mechanical and motorised counting points.

The second development phase is marked with the introduction of magnetic track contacts and motorised counting points.

The use of electric track contacts and electronic counting points can be defined as the third phase and current state of the art.

The first phase ended in 1939 and the second in 1963. From this one can deduce that the technology is very well developed.